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package project3;

import java.util.HashSet;
import java.util.Iterator;

import lex.Constant;


public class Domain
{
//Domain Implementations
    <a name="domain"/>
    public static HashSet<Constant> domain = new HashSet<Constant>();

//Constructors

//Queries
    <a name="iterator"/>
    public static Iterator<Constant> iterator()
    {
        return domain.iterator();
    }

    <a name="isEmpty"/>
    public static boolean isEmpty()
    {
        return domain.isEmpty();
    }

//Commands
    <a name="add"/>
    public static void add(Constant value)
    {
        assert value != null;
        domain.add(value);
    }

    <a name="reset"/>
    public static void reset()
    {
        domain = new HashSet<Constant>();
    }
}
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